Jerry, you could be full length sizing and still not touching the shoulder if the die is not set to do so. Joel above mentions the OAL of the case, if you can come up with a case length gauge that will measure the length of the case to the datum line, then you can properly set up the die to just bump back the shoulder. Otherwise, setting up the die is just hit or miss. I have had shell holders that were too "tall" to allow the die to be adjusted downward far enough, you'll just need to do some measuring of the sized cases and compare to your reamer print to see what you really have. I believe Redding sells shell holders of different "headspace measurements" in many calibers, other companies may as well. If you have a lathe, your shell holder can be faced off a thousandths at a time until your die will move the shoulder back. If you move the shoulder back too far, of course, you'll end up splitting the cases on fireforming, so go easy, check your progress often.
